John Lenthall was an American shipbuilder and naval architect. He was responsible for the construction and repair of United States Navy ships during the American Civil War (1861–1865), as well as in the years immediately before and after it. His career spanned the U.S. Navy's transition from sail to steam propulsion and from wooden ships to ironclads, and in retirement he participated in early planning for an eventual steel navy.

Samuel Humphreys was a noted American naval architect and shipbuilder in the early 19th century. He served the United States Navy as the Chief Constructor for the Navy from 1826 to 1846.